Alpha Diffuse Surface Shader issue

Hi!

I'm trying to build some custom shaders for my next title but I bumped into some problems. As you can see on picture below:

top left: looks relatively fine

other pictures shows issues with sorting rendered mesh. (whole "ground" is a single mesh)

for makign screenshot I have used a bit modified shader: Shader "Transparent/Diffuse" { Properties { _Color ("Main Color", Color) = (1,1,1,1) _MainTex ("Base (RGB) Trans (A)", 2D) = "white" {} }

 SubShader {
     Tags {"Queue"="Transparent" "IgnoreProjector"="True" "RenderType"="Transparent"}
     LOD 200
 
 CGPROGRAM
 #pragma surface surf Lambert alpha
 
 sampler2D _MainTex;
 fixed4 _Color;
 
 struct Input {
     float2 uv_MainTex;
 };
 
 void surf (Input IN, inout SurfaceOutput o) {
     fixed4 c = tex2D(_MainTex, IN.uv_MainTex) * _Color;
     o.Albedo = c.rgb;
     o.Alpha = c.a;
 }
 ENDCG
 }
 
 Fallback "Transparent/VertexLit"
 }

Bud I get exactly same issue with native version of this shader (its default Alpha-Diffuse.shader avaliable with unity)

issue dissapears as soon as I use:

     #pragma surface surf Lambert

instead of

     #pragma surface surf Lambert alpha

but I simply need to be able use transparency in shader.

Any help would be much appreciated.

Thank you